Flushing compositions



Patented Apr. 13 1954 UNITED STATES PATENT OFFICE FLUSHING COMPOSITIONS Oliver L. Brandes, Gibsonia, and Charles B. Pattinson, Jr., Oakmont, Pa., assignors to Gulf Research & Development Company, Pittsburgh, Pa., a corporation of Delaware No Drawing. Application March 9, 1950, Serial No. 148,746

This invention relates to improved flushing compositions for use in an internal combustion engine.

Flushing compositions are used in the crankcase of an internal combustion engine to remove gum, lacquer and carbonaceous deposits from cylinder walls, piston rings and grooves, oil lines, bearings, the oil pump screen, the crankshaft, and the walls of the crankcase.

Various flushing compositions have heretofore been disclosed for removing the undesirable deposits but the prior compositions have not been entirely satisfactory. Some of the prior compositions have exhibited good solvent properties but they have not had sumcientlubricating qualities to insure safe operation of an engine during the flushing period. Other compositions have possessed good lubricating characteristics but they have been inefficient cleansers. Still other compositions have had good lubricating characteristics combined with moderately good cleansing properties, but these compositions have not been generally accepted because of their tendency to stratify during storage.

The present invention is based upon particularly effective flushing compositions having good engine cleaning properties combined with good lubricating characteristics, and resistance against stratification during the normal handling, transportation, and storage of these compositions. The compositions of the invention are suitable for use not only in automotive engines but also in diesel and aircraft engines. I M The improved flushing compositions of our invention consist essentially of a homogeneous mixture of water, a water-soluble metallic soap, lubricating oil, a halogenated hydrocarbon, a monohydroxy monocyclic phenol, and an emulsifier.

The detergent used according to this invention is a water-soluble metallic soap of a fatty acid such as the soda soap or the potash soap of oleic acid, palmitic acid, linolenic acid, capric acid, linoleic acid, and mixtures thereof. The water content of the soap is an important factor in preparing the compositions of this invention. For instance, we have found that commercially attractive, non-stratifying compositions result only when the water content of the soap does not exceed about 4=0weight per cent. While compositions prepared from soaps containing more than 40 per cent and'as much as 60 per cent by weight of Water are satisfactory'insofar as their cleansing properties are concerned, they are not always commercially desirable in that they may stratify upon standing. Therefore. the compositions of our invention are prepared from soaps containing not more than about 40 per cent by Weight of water and advantageously between about 20 and about 40 per cent by Weight of water. The soap, including its water content, constitutes from about 5 per cent to about 40 per cent by Weight of the flushing composition. The soap aids in keeping the particles of sludge and carbonaceous materials in suspension after they have been removed from the engine parts.

Depending upon the Water content of the soap and the amount of the soap used, additional water may or may not be required. Based upon the total weight of the flushing composition, the water should be present in an amount between about 2 and about 30 Weight per cent. When additional water is required it is advantageously mixed with the soap to form a pasty to liquid detergent composition which may then be blended with the other constituents. The water is believed to tunetion as an activator for the soap and. apparently enables the soap to perform cleaning functions as well as those of a dispersant.

The halogenated hydrocarbon is employed in our compositions as a solvent for the carbonaceous deposits and to reduce the flammability of the compositions. The halogenated hydrocarbons which we prefer to use are those having a boiling point between about 35 and about 185 C. As examples of the halogenated hydrocarbons which we can use may be mentioned dichloroethylene, trichloroethylene, tetrachloroethylene, ethylene dichloride, propylene dichloride, trichloropropane, amylene dichloride, carbon tetrachloride, chloroform, and the chlorinated benzenes such as ortho-dichlorobenzene. While any of the above chlorinated compounds can be used in these compositions, the chlorinated benzenes because of their higher boiling points are preferred. The halogenated hydrocarbon is employed in amounts corresponding to about 1 to about 15 per cent by weight based upon the total weight of the flushing composition.

The monohydroxy monocyclic phenols are be lieved to function as solvents for removing the binder between the hard carbonaceous particles as Well as for removing these particles from the metal surfaces. The monohydroxy monocyclic phenols which we prefer to use have boiling points between about and about 300 C. Examples of the compounds having these desirable characteristics are phenol, ortho-cresol, meta-cresol, para-cresol, xylenols, and mixtures thereof especially commercially available mixtures, as well as their alkylated derivatives such as ethyl phenol, n propylphenol, isopropylphenol, n-

butylphenol, and the like. The monohydroxy monocyclic phenols are employed in an amount corresponding to about 15 to about 40 per cent by weight based upon the weight of the flushing composition.

The emulsifier used in the compositions of our invention may be any well-known commercially available emulsifier such as sorbitan monooleate,

diethanolamine, triethanolamine, higher alkanol amines, diethylene glycol, and esters thereof. The emulsifier aids the flushing composition to exist in one phase as a homogeneous mixture. The emulsifying agent is employed in an amount corresponding to about 0.1 to about 3.0 per cent based on the weight of the total composition.

The lubricating oil is used to impart lubricity to the flushing composition and to give it the desired viscosity. Naturally, the more viscous oils produce flushing compositions of higher viscosity. The lubricating oil may be derived from a parafiinic, naphthenic, or mixed base crude, or

the oil may be a synthetic oil having a viscosity within the range of a mineral oil of lubricating grade. If desired, a blend of oils of suitable viscosity may be employed instead of a single oil, by means of which any desired viscosity within the range of about 100 to 3500 SUS at 100 F. may be secured. The amount of the oil employed preferably constitutes from about percent to about 60 per cent by weight of the total composition.

In compositions of the type disclosed herein it is sometimes desirable to employ one or more of the so-called additive agents including oiliness and extreme pressure agents, viscosity index improvers, pour point depressants, foam inhibitors, and corrosion and oxidation inhibitors. Corrosion inhibitors are particularly desirable in flushing compositions used for the cleansing of aluminum pistons and corrodible alloy bearings,

such as copper-lead, cadmium-silver, and cadmium-nickel bearings. Corrosion inhibitors are also desirable in flushing compositions used in aircraft engines where lead-indium, high-lead babbitt, and other types of babbitt are frequently employed. The prevention of corrosion is also important in diesel engines because the minute orifices in the fuel injectors are easily plugged if they become corroded. In instances where corrosion is likely to occur, we may add an inhibitor in an amount corresponding to about 0.1 to 1.0 per cent based upon the total weight of the flushing composition. Among the corrosion inhibitors suitable for the purpose of our invention are dibenzyl disulfide, alkyl phenyl sulfides, alkyl phosphites, alkaryl phosphites, and sulfurized terpenes.

In compounding the compositions of the present invention, various blending. procedures may be used either at room temperature or atan elevated temperature. In accordance with one embodiment, the soap can first be heated and then admixed with the other ingredients in a suitable mixing device. If an additive agent is employed, it may be incorporated in the oil before the oil is added to the mixing device or it may be introduced into the mixing device together with the other ingredients.

The relative quantities of the various constituents in the flushing compositions of our invention may be varied within certain limits with out deleteriously affecting the beneficial effects and desirable properties of the compositions. A tabulation of the approximate maximum and minimum amounts of constituents used in pre- Specific examples of. flushing compositions within the scope of our invention are as follows:

Percent by Weight Composition Added Water 8 Potash soap (35% water) 30 20 Lubricating oil (1,900 SUV F. Texas Oil)... 20 49 Ortho-dichlorobenzene 5 9 Isopropylphenol 35 2O Triethanolamine 1 1 Suliurized tcrpcncs (30% sulfur) 1 1 The properties of the above flushing compositions are approximately as follows:

Composition Gravity, *API 9.1 12.8. Viscosity, SUS:

100 179 235. at 210 F... 44.3 48.4. Color, NPA 5+ 6+. Pour Point,F.; -30 -20. Flash Point, 006, F above 210.. above 210;

The compositions of the present invention have the important advantage of being, at least for all practical purposes, completely stable, as they show no evidence of Stratification when stored under normal conditions over long periods of time. For instance, composition .A and composition B given hereinabove by way of specific examples did not stratify even after standing for six months.

In order to determine the effectiveness of the flushing compositions of the present invention for removing gum, lacquer and carbonaceous deposits from an internal combustion engine, the following flushing procedure is employed. The used lubricating oil is drained from the crankcase. The engine is then torn down and examined for gum, lacquer and other carbonaceous deposits. After determining the condition of the engine, it is reassembled, the crankcase is filled to approximately its normal capacity with an engine flushing composition or, if desired, the crankcase may be filled to approximately twice its normal capacity with the flushing composition. In most cases, however, it is satisfactory to use the flushing composition in an amount equal to the normal crankcase capacity. The engine is then started and operated at fast idle (about 150033. P. M.) with no load for a periodof about 90 minutes, more or less, at a cooling jacket temperature of about F. The crankcase temperature obtained during this period preferably should not exceed about F. At the end of the 90 minute period the engine is stopped and the crankcase drained. The above procedure is then repeated using a light mineral lubricating oil for a period of about 20 minutes to remove the flushing composition held up in the engine and also to aid in draining from the engine any remaining deposits which have been loosened by the flushing composition. The enlue is then torn down and examined to determine the cleansing quality of the flushing composition.

In order to illustrate the advantageous results obtained when a flushing composition of our invention is employed to remove gum, lacquer and carbonaceous deposits from an internal combustion engine, the engine of a 1941 Chevrolet, having been driven approximately 41,000 miles, was subjected to the above-described cleansing procedure. The flushing composition employed was composition A set forth hereinabove. On disassembly of the engine prior to the start of the cleansing operation, the oil rings were noted to be about 95 per cent plugged with a heavy carbonaceous deposit; the oil screen was also about 95 per cent plugged with a heavy carbonaceous deposit. The crankcase oil pan contained some heavy sludge and was heavily lacquered. The piston skirts also were heavily lacquered. After the cleansing operation was completed, the oil rings were found to be 100 per cent cleaned; the oil screen was about 95 per cent clean, there remaining only a slight amount of sludge; and the crankcase oil pan was clean except for a small amount of sludge in the bottom which remained because of incomplete drainage of the crankcase. The piston skirts contained only a slight amount of varnish. A major proportion of the lacquer deposits was removed from the connecting rods, cylinder walls, bearings, rocker arm assembly and piston skirts. Composition B was equally as effective as composition A when used in the crankcase of a 1941 Chevrolet which had been driven about 46,500 miles. In further tests of other compositions within the scope of our invention on other makes and types of engines using a procedure similar to that described above, equally effective engine cleaning was obtained. When the composition A was used in a diesel engine it was found that excellent engine cleanliness was achieved and that no plugging of injector orifices occurred.

While our invention is described above with reference to various specific examples and embodiments, it will be understood that the invention is not limited to such examples and embodiments and may be variously practiced within the scope of the claims hereinafter made.

We claim:

1. A flushing composition consisting essentially of a homogeneous mixture of 5 to 40 per cent by weight of an alkali metal soap of a fatty acid containing not more than about 40 per cent by weight of water, to 60 per cent by weight of a mineral lubricating oil, 1 to per cent by weight of a halogenated hydrocarbon having a boiling point between about and about 185 C., 15 to per cent by weight of a monohydroxy monocyclic phenol having a boiling point between about and about 300 C.., 0.1 to 3.0 per cent by weight of an ethanolamine selected from the class consisting of diethanolamine and triethanolamine, and water in an amount sufficient to produce a flushing composition having a total water content between about 2 and about 30 weight per cent.

2. A flushing composition consisting essentially of a homogeneous mixture of 5 to 40 per cent by weight of a potash soap containing not more than about 40 per cent by weight of water, 10 to 60 percent by weight a mineral lubricating oil, 1 to 15 per cent by weight of orthodichlorobenzene, 15 to 40 per cent by weight of isopropylphenol, 0.1 to 1.0 per cent by weight of triethanolamine, and water in an amount sufficient to produce a flushing composition having a total water content between about 2 and about 30 weight per cent.

3. A flushing composition consisting essentially of a homogeneous mixture of 5 to 40 per cent by weight of a potash soap containing not more than about 40 per cent by weight of water, 10 to 60 per cent by weight of a mineral lubricating oil, 1 to 15 per cent by weight of ortho-dichl orobenzene, 15 to 40 per cent by weight of isopropylphenol, 0.1 to 1.0 per cent by weight of triethanolamine, 0.1 to 1.0 per cent by weight of sulfurized, terpenes, and water in an amount sufiicient to produce a flushing composition having a total water content between about 2 and about 30 weight per cent.

4. A flushing composition consisting of a homogeneous mixture of 8 per cent by weight of water, 30 per cent by weight of a potash soap containing 35 per cent by weight of water, 20 per cent by weight of a mineral lubricating oil, 5 per cent by weight of orthodichlorobenzene, 35 per cent by weight of isopropylphenol, 1 per cent by weight of triethanolamine, and 1 per cent by weight of sulfurized terpenes.

5. A flushing composition consisting of a homogeneous mixture of 20 per cent by weight of a potash soap containing 35 per cent by weight of water, 49 per cent by weight of a mineral lubricating oil, 9 per cent by weight of ortho-dichlorobenzene, 20 per cent by weight of isopropylphenol, 1 per cent by weight of triethanolamine, and 1 per cent by weight of sulfurized terpenes.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,165,498 Frank Dec. 28, 1915 1,340,315 Baum May 18, 1920 1,786,249 Kirschbraun Dec. 23, 1930 2,262,926 Edgar et al Nov. 18, 1941 2,279,001 Matheson Apr. 7, 1942 2,556,173 Ebel June 12, 1951 FOREIGN PATENTS Number Country Date 28,832 Great Britain of 1912 

1. A FLUSHING COMPOSITION CONSISTING ESSENTIALLY OF A HOMOGENEOUS MIXTURE OF 5 TO 40 PER CENT BY WEIGHT OF AN ALKALI METAL SOAP OF A FATTY ACID CONTAINING NOT MORE THAN ABOUT 40 PER CENT BY WEIGHT OF WATER, 10 TO 60 PER CENT BY WEIGHT OF A MINERAL LUBRICATING OIL, 1 TO 15 PER CENT BY WEIGHT OF A HALOGENATED HYDROCARBON HAVING A BOILING POINT BETWEEN ABOUT 35* AND ABOUT 185* C., 15 TO 40 PER CENT BY WEIGHT OF A MONOHYDROXY MONOCYCLIC PHENOL HAVING A BOILING POINT BETWEEN ABOUT 180* AND ABOUT 300* C., 0.1 TO 3.0 PER CENT BY WEIGHT OF AN ETHANOLAMINE SELECTED FROM THE CLASS CONSISTING OF DIETHANOLAMINE AND TRIETHANOLAMINE, AND WATER IN AN AMOUNT SUFFICIENT TO PRODUCE A FLUSHING COMPOSITION HAVING A TOTAL WATER CONTENT BETWEEN ABOUT 2 AND ABOUT 30 WEIGHT PER CENT. 